Processions of horse-drawn carriages at the Ceremony of the Presentation of Credentials on November 29th, 2011.
Ceremonial horse-drawn carriages welcome newly appointed ambassadors to Japan and convey them from the Meiji Seimei Kan Building to the Imperial Palace South Porch. Only a few countries worldwide, among them the United Kingdom and Spain, use horse-drawn carriages to welcome newly appointed ambassadors. In Japan, many ambassadors express a preference for the carriages over a conventional motorcade, attesting to the success of the ceremony in promoting international goodwill.
The ceremonial carriages used to welcome ambassadors are drawn by two horses and known as zagyoshiki. Most were manufactured from the end of the Meiji period to the beginning of the Showa period and have artistic value.
Processions of horse-drawn carriages are also used in Imperial Household ceremonies such as the accession of the Emperor to the throne and weddings of members of the Imperial Family.

Rules for joggers round Tokyo's Imperial Palace - Telegraph
Tokyo officials are compiling a series of rules to deal with a surge in the number of joggers exercising along the fringes of the Imperial Palace.
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Joggers along the route can take in views of the famous cherry trees of Chidorigafuchi, the picturesque northeastern moat of the palace, as well as the National Museum of Modern Art, parliamentary buildings and a distant Tokyo Tower.

However, more than 100 complaints have reportedly been received by police from pedestrians who claim to have been knocked by passing joggers, according to NHK reports.

The complaints combined with the growing popularity of the route have prompted the authorities in Tokyo to organise a series of meetings to discuss rules and guidelines to impose in order to ensure safety while jogging around the Imperial Palace.

Japanese man swims palace moat 'to meet emperor' - Emirates 24/7
A Japanese man who was arrested early Sunday inside the Imperial Palace grounds in Tokyo wearing only his underwear told police he swam across the moat to meet the emperor.
The man, in his 30s, did not seemed to have a clear political motive, said a duty officer at the Imperial Guard Headquarters.
"At the time of his arrest, around 4:34 am, he said 'I came to see the emperor. I swam'," the officer said.